:root {
  --bg: #f3f7fc;
  --paper: rgba(251, 253, 255, 0.94);
  --paper-strong: #ffffff;
  --ink: #17345b;
  --muted: #536c8f;
  --line: rgba(23, 52, 91, 0.1);
  --accent: #1059b6;
  --accent-deep: #0b3f80;
  --shadow: 0 24px 70px rgba(16, 89, 182, 0.12);
  --radius-lg: 28px;
  --radius-md: 20px;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at top right, rgba(16, 89, 182, 0.14), transparent 24%),
    linear-gradient(180deg, #fbfdff 0%, #f3f7fc 50%, #e8f0fb 100%);
  font-family: "Source Han Sans SC", "PingFang SC", "Helvetica Neue", sans-serif;
}
body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(23, 52, 91, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(23, 52, 91, 0.03) 1px, transparent 1px);
  background-size: 30px 30px;
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.5), transparent 88%);
}
.product-shell { width: min(1200px, calc(100vw - 40px)); margin: 0 auto; padding: 124px 0 0; }
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  width: 100%;
  padding: 18px 0;
  border-bottom: 1px solid var(--line);
  background: rgba(252, 254, 255, 0.84);
  backdrop-filter: blur(16px);
  box-shadow: var(--shadow);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: min(1200px, calc(100vw - 40px));
  margin: 0 auto;
  gap: 18px;
}
.header-brand {
  color: var(--ink);
  text-decoration: none;
  font-family: "Source Han Serif SC", "Songti SC", "Times New Roman", serif;
  font-size: 1.3rem;
  font-weight: 700;
}
.header-nav { display: flex; align-items: center; gap: 18px; }
.header-nav a { color: #426589; text-decoration: none; font-weight: 600; }
.lang-switch { position: relative; }
.lang-toggle {
  padding: 10px 14px;
  border: 1px solid rgba(23, 52, 91, 0.12);
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.74);
  font: inherit;
  cursor: pointer;
}
.lang-menu {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  display: grid;
  min-width: 160px;
  padding: 8px;
  border: 1px solid rgba(23, 52, 91, 0.12);
  border-radius: 14px;
  background: #fffdf9;
  box-shadow: 0 18px 40px rgba(23, 52, 91, 0.12);
  z-index: 20;
}
[hidden] { display: none !important; }
.lang-menu button {
  padding: 10px 12px;
  border: 0;
  border-radius: 10px;
  background: transparent;
  text-align: left;
  font: inherit;
  cursor: pointer;
}
.lang-menu button:hover { background: rgba(16, 89, 182, 0.08); }
.detail-layout { display: grid; gap: 18px; margin-top: 24px; }
.detail-hero, .section-panel { border: 1px solid var(--line); backdrop-filter: blur(16px); box-shadow: var(--shadow); }
.detail-hero {
  display: grid; grid-template-columns: minmax(0, 1.2fr) minmax(280px, 0.8fr); gap: 22px; align-items: end;
  padding: 34px 36px; border-radius: var(--radius-lg);
  background: linear-gradient(145deg, rgba(252, 254, 255, 0.96), rgba(233, 242, 255, 0.88)), var(--paper);
}
.back-link, .detail-kicker, .section-kicker { color: var(--accent); }
.back-link { display: inline-flex; align-items: center; margin-bottom: 18px; text-decoration: none; font-weight: 600; }
.detail-kicker, .section-kicker { margin: 0 0 14px; font-size: 12px; letter-spacing: 0.24em; text-transform: uppercase; }
.detail-hero h1, .section-title { margin: 0; font-family: "Source Han Serif SC", "Songti SC", "Times New Roman", serif; font-weight: 700; letter-spacing: -0.03em; }
.detail-hero h1 { font-size: clamp(2.8rem, 5.2vw, 5rem); line-height: 0.98; }
.detail-summary, .section-copy, .hero-meta p, .bullet-list li { line-height: 1.85; color: #426589; }
.detail-summary { max-width: 760px; margin: 18px 0 0; font-size: 1.08rem; }
.hero-meta { padding: 22px; border-radius: var(--radius-md); background: rgba(255, 255, 255, 0.72); border: 1px solid rgba(23, 52, 91, 0.08); }
.hero-visual { overflow: hidden; margin: 0 0 16px; border-radius: 14px; aspect-ratio: 16 / 10; border: 1px solid rgba(23, 52, 91, 0.08); background: rgba(255, 255, 255, 0.3); }
.hero-visual img { display: block; width: 100%; height: 100%; object-fit: cover; }
.hero-meta h2 { margin: 0 0 12px; font-size: 1.2rem; font-family: "Source Han Serif SC", "Songti SC", "Times New Roman", serif; }
.hero-meta p { margin: 0; }
.detail-grid { display: grid; grid-template-columns: repeat(12, minmax(0, 1fr)); gap: 18px; }
.section-panel { grid-column: span 6; padding: 24px; border-radius: var(--radius-md); background: var(--paper-strong); }
.section-panel-wide { grid-column: span 12; }
.section-title { font-size: 1.6rem; }
.section-copy { margin: 16px 0 0; }
.bullet-list { margin: 16px 0 0; padding-left: 18px; }
.bullet-list li + li { margin-top: 10px; }
.page-gallery { columns: 2; column-gap: 18px; margin-top: 18px; }
.gallery-item { margin: 0 0 18px; break-inside: avoid; }
.gallery-item img { display: block; width: 100%; border-radius: 14px; border: 1px solid rgba(23, 52, 91, 0.08); }
.gallery-item figcaption { margin-top: 10px; color: var(--muted); line-height: 1.7; }
.detail-footer { padding-top: 12px; }
.site-footer { position: relative; left: 50%; width: 100vw; margin-left: -50vw; margin-top: 30px; padding: 24px 0; border-top: 1px solid var(--line); background: linear-gradient(145deg, rgba(252, 254, 255, 0.96), rgba(233, 242, 255, 0.88)); box-shadow: var(--shadow); }
.footer-grid { display: grid; width: min(1200px, calc(100vw - 40px)); margin: 0 auto; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 22px; }
.footer-kicker { margin: 0 0 12px; font-size: 12px; letter-spacing: 0.18em; text-transform: uppercase; color: var(--accent); }
.footer-column h2 { margin: 0 0 12px; font-size: 1.3rem; font-family: "Source Han Serif SC", "Songti SC", "Times New Roman", serif; }
.footer-column p, .footer-links li, .footer-links a { color: #426589; line-height: 1.8; }
.footer-links { margin: 0; padding: 0; list-style: none; }
.footer-links li + li { margin-top: 8px; }
.footer-links a { text-decoration: none; }
.footer-subscribe { display: grid; gap: 10px; margin-top: 14px; }
.footer-subscribe input { width: 100%; padding: 12px 14px; border: 1px solid rgba(23, 52, 91, 0.12); border-radius: 12px; background: rgba(255, 255, 255, 0.8); font: inherit; }
.footer-subscribe button { padding: 12px 16px; border: 0; border-radius: 12px; color: #fff; background: linear-gradient(135deg, var(--accent), var(--accent-deep)); font: inherit; font-weight: 600; cursor: pointer; }
.cta-row { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 20px; }
.cta-link { display: inline-flex; align-items: center; justify-content: center; padding: 13px 18px; border-radius: 999px; text-decoration: none; font-weight: 600; transition: transform 180ms ease, background-color 180ms ease; }
.cta-link:hover { transform: translateY(-2px); }
.cta-link-primary { color: #fff; background: linear-gradient(135deg, var(--accent), var(--accent-deep)); }
.cta-link-secondary { color: var(--ink); background: rgba(255, 255, 255, 0.82); border: 1px solid rgba(23, 52, 91, 0.08); }
[data-reveal] { opacity: 0; transform: translateY(22px); transition: opacity 560ms ease, transform 560ms ease; }
[data-reveal].is-visible { opacity: 1; transform: translateY(0); }
@media (max-width: 980px) { .product-shell { width: min(100vw - 24px, 1200px); padding-top: 150px; padding-bottom: 0; } .detail-hero, .detail-grid { grid-template-columns: 1fr; } .section-panel, .section-panel-wide { grid-column: span 1; min-height: auto; } .footer-grid { width: min(100vw - 24px, 1200px); grid-template-columns: repeat(2, minmax(0, 1fr)); } .header-inner { width: min(100vw - 24px, 1200px); flex-wrap: wrap; } }
@media (max-width: 640px) { .detail-hero { padding: 28px 22px; } .page-gallery { columns: 1; } .header-nav { width: 100%; justify-content: space-between; } .lang-switch, .lang-toggle { width: 100%; } .site-header { padding: 14px 0; } .footer-grid { grid-template-columns: 1fr; } .cta-row { flex-direction: column; } .cta-link { width: 100%; } }